From: Kirill Miazine <km@krot.org>
Subject: Re: panic -- failed assertions
To: Martin Pieuchot <mpi@grenadille.net>
Cc: tech@openbsd.org
Date: Wed, 1 Jan 2025 00:06:54 +0100

Hello

I will do send to bugs@ next time.

• Martin Pieuchot [2024-12-31 10:26]:
> Hello Kirill,
> 
> Thanks for the report.  Unfortunately the report is incomplete.  If you
> can reproduce this issue, could you please send the information to bugs@
> making sure that you get the trace of the cpu that paniced?  See below.

I was following https://www.openbsd.org/ddb.html, but machine stopped responding when I did

machine ddbcpu 1

Next time I will get directly to the CPU with the asterisk.

> On 28/12/24(Sat) 22:15, Kirill Miazine wrote:
> > panic of a rather fresh amd64 snapshot, probably 3-4 days old
> > 
> > 
> > 
> > text below is OCR-ed with a phone, proofread by me:
> > 
> > panic(ffffffff8245eb59) at panic+0xc2
> > __assert(ffffffff82411a0a,ffffffff82438926,1c5,ffffffff823eb04f) at
> > __assert+0x29
> > amap_free(fffffd80506ac218) at amap_free+0x158
> > uvm_unmap_detach(ffff800032399418,0) at uum_unmap_detach+0xc3
> > sys_munmap(ffff8000ffff0338, ffff800032399530,ffff8000323994a0) at
> > sys_munmap+0x186
> > syscall(ffff800032399530) at syscall+0x620
> > Xsyscall() at Xsysca11+0x128
> 
> This is CPU0, not the one that paniced
> 
> > end of kernel
> > end trace frame: 0x7108d33299c0, count: 231
> > End of stack trace.
> > WARNING: SPL NOT LOWERED ON SYSCALL 72 8 EXIT 0 4
> > Stopped at savectx+0xae: movl $0,%gs:0x680
> > TID PID UID PRFLAGS PFLAGS CPU COMMAND
> > 462835 55586 1000 0x100033 0 3 ping
> > 495939 25031 1000 0x2200003 2 python3.12
> > *190552 6630 1001 0x3 0x4000000 0 syncthing
> > 374420 2561 0x14000 0x200 1 softnet0
> > savectx() at savectx+0xae
> > end of kernel
> > end trace frame: 0xZcb766910, count: 14
> > https://www.openbsd.org/ddb.html describes the minimum info required in bug
> > reports.
> > Insufficient info makes it difficult to find and fix bugs.
> > ddb{0} > show panic
> > cpu0: kernel diagnostic assertion "!rw_write_held(amap->am_lock)" failed:
> > file /usr/src/sys/uum/uum_amap.c", line 453
> > *срu3: kernel diagnostic assertion "off == trunc_page(off)" failed: file
> > "/usr/src/sys/uvm/uvm_page.c", line 888
> 
>    ^^^^ 
>   CPU3 is the one that one that interest us.  You can switch CPU in ddb
>   with "mach ddbcpu 3".
> 
> Thanks,
> Martin
> 
> 

-- 
    -- Kirill Miazine <km@krot.org>